This is my build of the ACA #1 ( see images attached).
Well: the ACA #1 is able to reproduce music (playing Diana Krall currently), but cannot compare to a well_designed ClassA/B Amplifier
(like the SYMASYM, for example) - in my ears.
I am missing "lust for life", emotion, dynamics, "deep black bass", but I will keep it, anyway, because its case fits very well on my desktop.
Best regards - Rudi_Ratlos
P.S.: I am operating the ACA #1 from a DELL PA10 19.5VDC /4.5A LAPTOP PSU.
Well: the ACA #1 is able to reproduce music (playing Diana Krall currently), but cannot compare to a well_designed ClassA/B Amplifier
(like the SYMASYM, for example) - in my ears.
I am missing "lust for life", emotion, dynamics, "deep black bass", but I will keep it, anyway, because its case fits very well on my desktop.
Best regards - Rudi_Ratlos
P.S.: I am operating the ACA #1 from a DELL PA10 19.5VDC /4.5A LAPTOP PSU.
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Thats what class A 'should' give you. What are your speakers?
It made a pair of minimus 7's sound huge for me....
Nice build btw!
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Hi, I suffered the same...
Hi,
When I finished tha ACA, I tried it with a Rega RS1 and with a Monitor Audio Silver RX1 and suffered the same symptoms as you. I asked here in the forum and some one told me that those speakers where not suitable for this amp ( 5 Watts ) although it was class A. Then I tried a full range speaker based on the Fostex FE83En and the sound was awesome but lacking a little of bass due to the nature of this speaker. Already I am using a full range based on markaudio CHR-70 with better bass and better dynamics. I feel really happy with this little amp. Right now I am building a F5 amp but I think I have gone overboard and really not need the F5... But still. This is how this hobby behave....
I have ready a traditional power supply to try if the amp improves over the SMPS brick supplied as standard, but I have to find some time to implement it inside the case. Too many projects open at the same time...
Best regards,
Jorge
Hi,
When I finished tha ACA, I tried it with a Rega RS1 and with a Monitor Audio Silver RX1 and suffered the same symptoms as you. I asked here in the forum and some one told me that those speakers where not suitable for this amp ( 5 Watts ) although it was class A. Then I tried a full range speaker based on the Fostex FE83En and the sound was awesome but lacking a little of bass due to the nature of this speaker. Already I am using a full range based on markaudio CHR-70 with better bass and better dynamics. I feel really happy with this little amp. Right now I am building a F5 amp but I think I have gone overboard and really not need the F5... But still. This is how this hobby behave....
I have ready a traditional power supply to try if the amp improves over the SMPS brick supplied as standard, but I have to find some time to implement it inside the case. Too many projects open at the same time...
Best regards,
Jorge
Rudi;
I used your layout, thank you for that.
Am using the amp for headphones and it is way better than the other amps that I have tried...
pretty much the opposite of what you described.......???
Although I can only compare it to what I have... Cmoy, A47, O2, Sony & Marantz receivers and an F5...
The F5 is overkill but great, don't like the rest much for phones.
will have to try speakers some time.....
I used your layout, thank you for that.
Am using the amp for headphones and it is way better than the other amps that I have tried...
pretty much the opposite of what you described.......???
Although I can only compare it to what I have... Cmoy, A47, O2, Sony & Marantz receivers and an F5...
The F5 is overkill but great, don't like the rest much for phones.
will have to try speakers some time.....
The 200 VA transformer is now installed on my build. Thought it might be a bit smaller as a 15 V but I guess 200 means BIG. The SPL is not noticeably higher than either the external pods or the 25 VA toroid.
What has really impressed me is improvement in the 3D aura produced. It was totally unexpected and nothing has changed but the size of the transformer. There is still not a lot of depth behind the speakers, but the mids and lows completely surround/engulf the listener. I tried several selections and the improvement is consistent. Maybe on of the gurus could add some light here. I suspect the low, if not non-existent distortion is allowing those little sound wave guys to bounce around the room totally unencumbered.
For SPL, I have previously asked about using a pre with the ACA but didn't get much feedback. As a nubee discrete builder my concern it pushing too far, too fast and thereby violating some temperature factor/limit.
I intend to reconfigure what I have for use with earphones primarily because of the total cleanliness of the output. With the over-sized transformer the possibility of adding two more ACAs and bi-amping also comes to mind. Everything is there at great quality - just not a lot of it.
or.....
(from zrk971 over on the Foam Core Board thread ).... "Bigger fish ........ using Lowes 1 in thick isocyanurate foam sheathing! Build a 10 Hz 110 dB at 1 watt monster.""
P.S. I'm starting to believe the whole ACA thing is a devious conspiracy by Nelson Pass, as I too have ordered a set of F5 boards from the diyAudio store. What was that thing about the Pied Piper????
What has really impressed me is improvement in the 3D aura produced. It was totally unexpected and nothing has changed but the size of the transformer. There is still not a lot of depth behind the speakers, but the mids and lows completely surround/engulf the listener. I tried several selections and the improvement is consistent. Maybe on of the gurus could add some light here. I suspect the low, if not non-existent distortion is allowing those little sound wave guys to bounce around the room totally unencumbered.
For SPL, I have previously asked about using a pre with the ACA but didn't get much feedback. As a nubee discrete builder my concern it pushing too far, too fast and thereby violating some temperature factor/limit.
I intend to reconfigure what I have for use with earphones primarily because of the total cleanliness of the output. With the over-sized transformer the possibility of adding two more ACAs and bi-amping also comes to mind. Everything is there at great quality - just not a lot of it.
or.....
(from zrk971 over on the Foam Core Board thread ).... "Bigger fish ........ using Lowes 1 in thick isocyanurate foam sheathing! Build a 10 Hz 110 dB at 1 watt monster."
"P.S. I'm starting to believe the whole ACA thing is a devious conspiracy by Nelson Pass, as I too have ordered a set of F5 boards from the diyAudio store. What was that thing about the Pied Piper????
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Oh absolutely- he told me so! Nearly done...
ACA is warming up for the bias adjustments, just need to get the holes drilled for the switches in the front plate.
Testing on speakers later tonight... as seen on the pic, the power jacks are mounted on a piece of plastic screwed to the back plate, so chassis not at ground. No feedback to my earlier question, so went ahead - no smoke and I'm still here...
ACA is warming up for the bias adjustments, just need to get the holes drilled for the switches in the front plate.
Testing on speakers later tonight... as seen on the pic, the power jacks are mounted on a piece of plastic screwed to the back plate, so chassis not at ground. No feedback to my earlier question, so went ahead - no smoke and I'm still here...
Listening impressions
My system has a B1 clone feeding the power section of an Accuphase E-206 driving a pair of bofu + supertweeter full range speakers.
Swapping in the ACA, I noticed a larger sound stage - width, depth and especially height. Separation of instruments and singers was greater, I was made more aware of the surrounding space.
Top end was highlighted more with greater sibilance, but not to the point of objection. Bass was tight and well articulated, and the mids were nicely fleshed out. The sound seemed more liquid, the Accuphase seemed drier.
Overall, very pleased with the results so far...
Thank you Nelson and the Diyaudio team for making this all possible...
My system has a B1 clone feeding the power section of an Accuphase E-206 driving a pair of bofu + supertweeter full range speakers.
Swapping in the ACA, I noticed a larger sound stage - width, depth and especially height. Separation of instruments and singers was greater, I was made more aware of the surrounding space.
Top end was highlighted more with greater sibilance, but not to the point of objection. Bass was tight and well articulated, and the mids were nicely fleshed out. The sound seemed more liquid, the Accuphase seemed drier.
Overall, very pleased with the results so far...
Thank you Nelson and the Diyaudio team for making this all possible...
Very close now..
While Mark has been busy in San Francisco preparing the next batch of ACA kits, I've been busy in Italy working with fellow audio fanatic Andrea at Hifi2000 on some really nice cases to complete the amps.
We hope you like the look of them. This is just a set of teaser photos of some prototypes and some small details will change (including the addition of some custom CNC detail work on the front and silk screening on the back) but I can assure you they look gorgeous in the flesh. More photos to come later this week!
Durable, high quality Dupont gloss and matte enamels, the usual Hifi2000 fit and finish and and of course everything will just bolt straight in. We did a lot of listening tests on various configurations, swapping DACs, Speakers, Amps, Analog/Digital sources, Single and dual PSUs, and using 4 to create a quad-mono biamped setup which had them punching way above their weight, especially on the larger speakers.
We've sourced some special packaging just for these cases which will provide an excellent guarantee of them arriving shiny and new.
I hope to have everything set up to start pre-sales this week with delivery a few weeks after. The standard color will be a 10mm silver front panel and matt black enamel, to match the other chassis we have in stock. However, we'll be offering a limited run in the presale with a 10mm black front panel and the body a beautiful and durable, high quality enamel finish in a shade of red whose name we can't mention but is commensurate with the quality of the finish Let's just call it "Electric Red"
While Mark has been busy in San Francisco preparing the next batch of ACA kits, I've been busy in Italy working with fellow audio fanatic Andrea at Hifi2000 on some really nice cases to complete the amps.
We hope you like the look of them. This is just a set of teaser photos of some prototypes and some small details will change (including the addition of some custom CNC detail work on the front and silk screening on the back) but I can assure you they look gorgeous in the flesh. More photos to come later this week!
Durable, high quality Dupont gloss and matte enamels, the usual Hifi2000 fit and finish and and of course everything will just bolt straight in. We did a lot of listening tests on various configurations, swapping DACs, Speakers, Amps, Analog/Digital sources, Single and dual PSUs, and using 4 to create a quad-mono biamped setup which had them punching way above their weight, especially on the larger speakers.
We've sourced some special packaging just for these cases which will provide an excellent guarantee of them arriving shiny and new.
I hope to have everything set up to start pre-sales this week with delivery a few weeks after. The standard color will be a 10mm silver front panel and matt black enamel, to match the other chassis we have in stock. However, we'll be offering a limited run in the presale with a 10mm black front panel and the body a beautiful and durable, high quality enamel finish in a shade of red whose name we can't mention but is commensurate with the quality of the finish
Let's just call it "Electric Red" Attachments
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Wow, looks great! That must be famous Italian sports car red....
Wasn't planning on doing an Amp Camp Amp, but when I see this....
Also nice to see a picture of Andrea, he is finishing a frontpanel I ordered, so ít's nice to see a picture of someone you have email conversation with...
Keep on the good work!
Wasn't planning on doing an Amp Camp Amp, but when I see this....
Also nice to see a picture of Andrea, he is finishing a frontpanel I ordered, so ít's nice to see a picture of someone you have email conversation with...
Keep on the good work!
Let's just call it... "Electric Red"
And yes I do know what you mean, they look "inspiringly" good
Andrea is a great guy and a really passionate DIYer. It's a family business in every sense and they are intensely proud of their ability to make the highest quality product on the market.
We may be able to have a few more options than normal for the presale. I'll start a discussion thread on that later in the week and link to it from this thread. You'll be able to voice your request there and see who else chimes in - if there is enough demand for a certain look then it may be a possibility.